The invention relates to a pressure measuring glow plug. In pressure measuring glow plugs, the glow pin can move relative to the plug housing through exposure to the combustion chamber pressure. The higher the combustion chamber pressure, the further the glow pin is pushed into the housing. The pressure acting on the glow pin or the pressure-dependent position of the glow pin relative to the housing is acquired with a sensor, for example with a piezoelectric sensor or a strain gauge.
In such a pressure measuring glow plug, the glow pin has to be electrically connected to the center pole. This is usually done with a contact spring. Within the framework of this disclosure, it was recognized that the contact spring can be a source of interference signals, which detract from the accuracy of a pressure measurement.